Plotting instrument



r. R. SANTORI.

PLGTTING INSTRUMENT. APPUCATIQN FILED DE C.10. 1920.

1,419,645 I Patented June 13, 1922.

WITNESS INVENTOR m/v/r If. jmvram A TTORNE Y8 PAT? FE TEE.

FRANK R. SANTORI, OF NEW YORK, N. Y.

PLO'ITING INSTRUMENT.

Application filed December 10, 1920. Serial No. 429,631.

T 0 all 'LO/LOWZ it may concern:

Be it known that I, FRANK R. SANTORI, a citizen of the United States,and a resident of the borough of Manhattan, city and State of New York,have invented certain new and useful Improvements in PlottingInstruments, of which the following is a specification.

This invention relates to a plotting instrument and is particularlyadvantageous for use in making nautical calculations.

In the drawings Fig. l isa perspective View of the instrument; Fig. 2 isa top plan view thereof; Fig. 3 is an enlarged View of the means forslidably holding and retaining one of the elements of the instru-..

ment in position.

The instrument comprises the customary dividers A with the legs 1 and 2pivotally connected at 3. One of the legs, as for in stance the leg 2,is provided with a member 4, slidably mounted in the guide way 5. Apointer or indicator 6 is secured at a rlght angle to an end of themember 4 and is intended for use in connection with the dividers forinstance in plotting the position of a ship at sea.

The member 4 is preferably rectangular in a cross-section and fits quitesnugly in the guide way 5, which in such case is also rectangular incross-section, whereby the member 4 is secured against turning. Themember 4: may thus be moved to a given position on the chart in relationto a position of the dividers A. The member 4 may be secured-at anyextended position from the dividers A by the set-screw 7.

It is to be observed that the guide way 5 is at a right angle to theaxis of the leg 2 and consequently the axis of the adjustable member atis at right angles to the axes of the legs 1 and 2, (their axes being inthe same plane). The relative position of the members 1, 2 and 4;, whenthe indicator 6 is adjusted to a point spaced from the leg 2, willalways result in laying down a right angle defined by a straight linedrawn through the points of the legs 1 and 2 and an intersectingstraight line drawn through the points of the leg 2 and the indicator 6.

While the illustrated example shows a preferred arrangement of theplotting instrument, it will, of course, be understood that the same maybe replaced by any other construction which includes an intermediatepointer corresponding to the one which forms the continuation of the leg2 and additional pointers corresponding respectively to the one whichconstitutes a continuation of the leg 1, and to the pointer 6 andconnected with said intermediate pointer so as to be adjustablerelatively thereto in directions transverse to each other upon a commonplane, in combination with means for fixing one of said additionalpointers in its adjusted position against movement relative to the saidintermediate pointer.

What I claim is:

1. A plotting instrument comprising an intermediate pointer, twoadditional pointers connected with said intermediate pointer, andadjustable relatively thereto in directions transverse to each otherupon a common plane, all of said pointers having a fixed relation toeach other in which the active ends thereof are capable at all times ofcoincidentally engaging a surface in said plane, and means for fixingone of said ad ditional pointers in its adjusted position againstmovement relatively to said intermediate pointer.

2. A plotting ,instrument comprising a pair of legs pivotally connectedat one end, a member slidably mounted upon one of said legs andadjustable relatively thereto in directions at right angles to animaginary line connecting the free ends of said legs, a pointer carriedby said member and adjustable thereby to different distances from saidleg without changing the angular position of said member relatively tothe leg upon which it is mounted and means for securing said member inan adjusted position.

3. A plotting instrument comprising a pair of legs pivotally connectedat one end, a member slidably mounted upon one of said legs andadjustable relatively thereto in directions parallel to the pivot aboutwhich said legs are pivotally movable, said member being fixed againstrotation about its axis relatively to the leg upon which it is mounted,and a pointer carried by said member and adjustable thereby to differentdistances from said leg Without affecting the parallelism of said memberto said pivot.

In testimony whereof I have hereunto set my hand.

FRANK R. SANTORI.

